1. Field of the Invention
This invention relates to a spark plug with an electrically insulating ceramic insulator.
2. Description of the Related Art
In these conventional popular spark plugs with a spark gap in air malfunctions often occur due to fouling; they include restart and cold starting problems which due to low shunt resistance of the insulator base which is caused by electrically conductive combustion residues (carbon) lead to malfunction of the spark plug.
Therefore, the object of the invention is to make available a spark plug with cold starting properties which have been greatly improved, in which the aforementioned problems are greatly reduced.
The object in accordance with the invention is achieved by providing a spark plug with an electrically insulating ceramic insulator, a metallic spark plug body, a ground electrode and a middle electrode centrally located in a hole of the ceramic insulator, whereby a peripheral tip is formed around the ignition-side end area on the periphery of the middle electrode, the peripheral tip encompassing the middle electrode in an annular manner.